Travel Center

Traction & Chain Laws

When weather conditions warrant, CDOT implements Passenger Vehicle Traction and Chain Laws. Motorists will be alerted to an active Traction Law or Chain Law by highway signage, and traffic/roadway condition alerts. For more information, download the Traction Law Fact Sheet. 

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snow2@2x.pngTraction Law

During winter storms, or when conditions require, CDOT will implement the Traction Law. During a Traction Law, all motorists are required to have EITHER:

  1. 4WD or AWD vehicle and 3/16” tread depth
  2. Tires with a mud and snow designation (M+S icon) and 3/16” tread depth 
  3. Winter tires (mountain-snowflake icon) and 3/16” tread depth 
  4. Tires with an all-weather rating by the manufacturer and 3/16” tread depth
  5. Chains or an AutoSock®

Traction Law Tree

Click here to view the Traction Law Tree and put your vehicle to the test.

Traction Law Updates
In 2019, Gov. Jared Polis signed House Bill 19-1207 into law, updating the Traction Law.

What’s Changed?

  • From Sept. 1 to May 31, the Traction Law is always active on I-70 from Dotsero to Morrison.
  • The minimum tread depth for tires on all vehicles increased to 3/16”.

These updates are meant to alleviate delays and crashes along this corridor during the peak winter driving season. Electronic signs will notify the public when there are additional closures or restrictions along I-70 in addition to the Traction Law.

    Passenger Vehicle Chain Law 

    During severe winter storms, CDOT will implement the Chain Law. This is the final safety measure before the highway is closed.

    When the Chain Law is in effect, every vehicle must have chains or an AutoSock®.


    • Motorists driving with inadequate equipment when a Traction Law or Chain Law is in effect could be fined more than $130.
    • If a motorist blocks the roadway because they have inadequate equipment when a Traction Law or Chain Law is in effect, he/she could be fined more than $650.


    The laws focus on passenger vehicles. Commercial vehicles have their own restrictions. For more information on the Chain Law for commercial vehicles, visit

    The Colorado State Patrol (CSP) will enforce the Traction and Chain Laws as secondary offenses. This means CSP can only cite motorists if they crash and/or cause traffic delays and are not compliant with the laws.

    An AutoSock® is an alternative traction device made of hi-performance textile material. AutoSocks® fit over a vehicle’s front (driving) tires to provide adequate traction in snowy and icy conditions. For more information, or to purchase an AutoSock®, visit

    Yes, CDOT can implement the Traction and Chain Laws on all state highways.

    Colorado: The Official State Web Portal